The present invention relates to mounting a flat wire electrical cable used for carrying power into components on rotatable elements, such as a manipulator swing arm or handler arm without use of slip rings or other expensive connections. The arm shown is for handling compact discs, or other discs that have center holes used for lifting, in a pick and place type operation.
Rotating a laterally extending disc lift arm that is used for handling components about an upright axis in small spaces requires transferring power to operate grippers at the outer end of the arm while the arm is permitted to rotate. Slip rings have been used for transmitting power, but slip rings are expensive, sometimes unreliable and require maintenance and cleaning. Additionally, various coiled cords similar to a telephone hand piece cord have been used, but tangling continues to be a problem. Unrestricted rotational movement without having the coil or the cord move from side to side and get in the way of moving parts is a problem as well.
The present invention relates to providing a mounting of an electrical cable carrying power between a stationary frame and a rotating member, such as an arm that has a gripper at its outer end. As shown, a multi conductor flat wire cable is formed in a coil about an axis parallel to the axis of rotation of the arm. The arm is mounted on an outer end of a column that extends from a platform or support. Power is required for components, such as a gripper on the arm. The power cable coil is supported on a platform surface and one end of the coil is clamped to the platform. The other end of the coil, which preferably has multiple turns, is guided about the rotating element, as shown, and secured thereto. The coil is loose and as the rotating element rotates, the coil tightens and loosens without tangling or excessive displacement.
Specifically, the coiled cable is used with a compact disc printing apparatus where blank discs are retained in a stack, and are held by a grip on a rotating arm supported on a column, moved to a printing station, deposited in the station, and when printed, the disc is moved from the initial stack to a finished disc stack. The finished disc stack or station is on an opposite side of the print station from the blank disc station, but the finished disc station can be adjacent the blank disc station as well. The apparatus can be used to record and print discs by adding a recording station to the sequence.
Rotation of the arm about the axis of the support column is at times greater than 180xc2x0, and with the present invention, a full 360xc2x0 rotation can be obtained with little additional, if any, space by utilizing the coil of the flat wire cable of the present invention.
A length of flat wire cable extends below the support platform through an opening in the platform. The cable is secured to the support platform, as stated, and passed up through the opening to a generally horizontal upper surface of the support platform. The cable is fixed to the edges of the opening and is folded so the plane of the flat cable above the platform is perpendicular to the platform upper surface and formed into a loose coil. The coil of cable is formed around the opening and the free end portion of the cable is passed under a retaining or guide tab on the platform, and then extends around upright supports of the rotating column or tower which is adjacent to the platform. The cable is secured in place on the upright supports of the column or tower, with the plane of the cable length between the coil and the tower still is positioned perpendicular to the supporting surface of the platform. The free end of the cable then can be run up to the top of the column or tower, where the arm is positioned and connected to carry power to components on the arm.
Other components on the arm can be powered, other than a gripper, utilizing the unique positioning and handling of a take up coil for the electrical power transmission cable.